| Itthipol Nonsiri | |
| Fullname: | Itthipol Nonsiri |
| Birth Date: | 15 April 1979 |
| Birth Place: | Ubon Ratchathani, Thailand |
| Position: | Defender |
| Youthyears1: | 1998–1999 |
| Youthclubs1: | Port Authority of Thailand |
| Years1: | 2000–2012 |
| Clubs1: | Thai Port |
| Caps1: | 118 |
| Goals1: | 1 |
| Years2: | 2012–2014 |
| Clubs2: | Yasothon |
| Caps2: | 29 |
| Goals2: | 0 |
| Manageryears1: | 2019 |
| Managerclubs1: | Port B |
| Manageryears2: | 2021–2022 |
| Managerclubs2: | Trang |
| Manageryears3: | 2022 |
| Managerclubs3: | Kasetsart (interim) |
| Manageryears4: | 2023 |
| Managerclubs4: | STK Muangnont |
| Manageryears5: | 2023– |
| Managerclubs5: | Marines |
Itthipol Nonsiri (th|อิทธิพล นนท์ศิริ; born 15 April 1980) is a former Thai footballer. He was played for Thai Port FC and he was named club captain for the 2009 season.
He came on as a substitute in the 2010 Thai League Cup final and won a winner's medal after Thai Port defeated Buriram PEA F.C. 2–1.